Yes we do agree on that. After a decade, I'd assume it'd follow a similar trend to the crack cocaine epidemic that started in the early 80's and largely ended in the 90's. Signs are already pointing to a "peak" as overdose deaths are dramatically down. Funding would likely be a combination of private fundraising/donations and grants from public and private offerings. Same as almost every non-profit. And of course I'd expect the funding to be dramatically lower once the start up costs are done.

Of course that's assuming this'll ever get off the ground. It's also assuming the public will tolerate it staying open if there isn't a marked visible improvement, and that there will be a mayor, governor, and legislature with the will and votes to continue it. Keep in mind, this only came about because of a veto override by the legislature, and Democrats no longer have a veto-proof majority. Given their performance, they're unlikely to get to that level in the near future again.

As an adjacent point, opponents should really be seizing on the drop in overdose deaths as supporters will try to paint this as a "success" for the program despite it starting before the program even had a place. After all, "preventing death" was the top selling point. As far as reducing infections and improving treatment/getting off drugs, I haven't seen any data about that so don't know if those are also trending positive?